Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
BMC Evol Biol
2007 Nov 12;7:222. doi: 10.1186/1471-2148-7-222.
Show Gene links
Show Anatomy links
Functional evolution of the vitamin D and pregnane X receptors.
Reschly EJ
,
Bainy AC
,
Mattos JJ
,
Hagey LR
,
Bahary N
,
Mada SR
,
Ou J
,
Venkataramanan R
,
Krasowski MD
.
???displayArticle.abstract???
The vitamin D receptor (VDR) and pregnane X receptor (PXR) are nuclear hormone receptors of the NR1I subfamily that show contrasting patterns of cross-species variation. VDR and PXR are thought to have arisen from duplication of an ancestral gene, evident now as a single gene in the genome of the chordate invertebrate Ciona intestinalis (sea squirt). VDR genes have been detected in a wide range of vertebrates including jawless fish. To date, PXR genes have not been found in cartilaginous fish. In this study, the ligand selectivities of VDRs were compared in detail across a range of vertebrate species and compared with those of the Ciona VDR/PXR. In addition, several assays were used to search for evidence of PXR-mediated hepatic effects in three model non-mammalian species: sea lamprey (Petromyzon marinus), zebrafish (Danio rerio), and African clawed frog (Xenopus laevis). Human, mouse, frog, zebrafish, and lamprey VDRs were found to have similar ligand selectivities for vitamin D derivatives. In contrast, using cultured primary hepatocytes, only zebrafish showed evidence of PXR-mediated induction of enzyme expression, with increases in testosterone 6beta-hydroxylation activity (a measure of cytochrome P450 3A activity in other species) and flurbiprofen 4-hydroxylation activity (measure of cytochrome P450 2C activity) following exposure to known PXR activators. A separate assay in vivo using zebrafish demonstrated increased hepatic transcription of another PXR target, multidrug resistance gene (ABCB5), following injection of the major zebrafish bile salt, 5alpha-cyprinol 27-sulfate. The PXR target function, testosterone hydroxylation, was detected in frog and sea lamprey primary hepatocytes, but was not inducible in these two species by a wide range of PXR activators in other animals. Analysis of the sea lamprey draft genome also did not show evidence of a PXR gene. Our results show tight conservation of ligand selectivity of VDRs across vertebrate species from Agnatha to mammals. Using a functional approach, we demonstrate classic PXR-mediated effects in zebrafish, but not in sea lamprey or African clawed frog liver cells. Using a genomic approach, we failed to find evidence of a PXR gene in lamprey, suggesting that VDR may be the original NR1I gene.
Figure 1. Chemical structures of 1α,25-(OH)2-vitamin D3 (calcitriol), 1α-hydroxyvitamin D2, testosterone, 5α-petromyzonol 24-sulfate (major sea lamprey bile salt), 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and 6-formylindolo [3,2-b]carbazole. Select bond positions are numbered for the vitamins, testosterone, and 5α-petromyzonol 24-sulfate, and the lettering of the steroidal rings is indicated for calcitriol, 1α-hydroxyvitamin D2, and testosterone. The carbon atoms numbered for testosterone indicate the sites of hydroxylation in the species studied in this report.
Figure 2. Concentration-response curves for activation of VDRs by vitamin D derivatives and 6-formylindolo [3,2-b]carbazole. The ordinate represents activation of VDR, relative to vehicle control, and normalized to the maximal activator (0.5 μM calcitriol for mouse and sea lamprey VDRs; 1 μM calcitriol for human, frog, and zebrafish VDRs; 20 μM 6-formylindolo [3,2-b]carbazole for Ciona intestinalis VDR/PXR). (A)-(E) Human (●), mouse (■), frog (○), zebrafish (□), and sea lamprey (◇) VDRs are all activated by vitamin D derivatives while the Ciona intestinalis VDR/PXR (Δ) is insensitive to all vitamin D compounds. (F) The planar molecule 6-formylindolo [3,2-b]carbazole activates most vertebrate VDRs (i.e., all except zebrafish VDR) weakly and the Ciona VDR/PXR at low micromolar concentrations.
Figure 3. Enzyme induction in cultured primary zebrafish hepatocytes. (A) 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and 3-methylcholanthrene (3-MC) both increase EROD activity in zebrafish hepatocytes, relative to vehicle-only control, following a 48-hour exposure. In contrast, 3,3'-diindoylmethane (DIM) causes a reduction in EROD activity relative to vehicle-only control. (B) 5α-androstan-3α-ol (androstanol), 5α-cyprinol 27-sulfate, phenobarbital, and TCDD cause a concentration-dependent increase in testosterone 6β-hydroxylation activity in primary zebrafish hepatocytes, relative to vehicle control, following a 48-hour exposure. (C) Androstanol, 5α-cyprinol 27-sulfate, phenobarbital, and TCDD all activate recombinant zebrafish PXR using a luciferase-based reporter assay system in HepG2 liver cells. All values are normalized relative to 20 μM androstanol (which is assigned an efficacy of 1) and to β-galactosidase expression. (D) Phenobarbital (PB; 2 and 3 mM), TCDD (1 nM), and androstanol (0.2 mM) all increase flurbiprofen 4-hydroxylation activity in primary zebrafish hepatocytes, relative to vehicle control, following a 48-hour exposure.
Figure 4. Phylogeny of vitamin D receptors (VDRs, NR1I), pregnane X receptors (PXRs,NR1I2), and constitutive androstane receptors (CARs, NR1I3). See Methods for details on the phylogenetic analysis. Four key evolutionary transitions in ligand sensitivity (i.e., ability to be activated by ligands) are proposed and indicated by the labels A, B, C, and D underneath four branches. Label A indicates loss of ligand sensitivity in the Xenopus frog PXRs relative to other PXRs. The Xenopus laevis and Xenopus tropicalis PXRs have narrow ligand sensitivity (essentially to benzoate compounds only) compared to other vertebrate PXRs. Label B indicates broadening of ligand specificity relative to the ancestral receptor. This is supported by the broader ligand specificity of vertebrate PXRs relative to the Ciona intestinalis VDR/PXR. Label C indicates acquisition of sensitivity to certain bile acids, particularly lithocholic acid and its derivatives, in mammalian VDRs. All non-mammalian VDRs studied so far are insensitive to bile salts. Label D indicates acquisition of sensitivity to vitamin D, a property of all vertebrate VDRs but not the Ciona VDR/PXR.
Bertilsson,
Identification of a human nuclear receptor defines a new signaling pathway for CYP3A induction.
1998, Pubmed
Bertilsson,
Identification of a human nuclear receptor defines a new signaling pathway for CYP3A induction.
1998,
Pubmed
Bhattacharya,
Coordinate regulation of fibrinogen subunit messenger RNA levels by glucocorticoids in primary cultures of Xenopus liver parenchymal cells.
1991,
Pubmed
,
Xenbase
Blumberg,
BXR, an embryonic orphan nuclear receptor activated by a novel class of endogenous benzoate metabolites.
1998,
Pubmed
,
Xenbase
Blumberg,
SXR, a novel steroid and xenobiotic-sensing nuclear receptor.
1998,
Pubmed
Bryan,
The sea lamprey (Petromyzon marinus) has a receptor for androstenedione.
2007,
Pubmed
Cai,
The farnesoid X receptor FXRalpha/NR1H4 acquired ligand specificity for bile salts late in vertebrate evolution.
2007,
Pubmed
Christakos,
New insights into the mechanisms of vitamin D action.
2003,
Pubmed
Ciesielski,
Structural investigation of the ligand binding domain of the zebrafish VDR in complexes with 1alpha,25(OH)2D3 and Gemini: purification, crystallization and preliminary X-ray diffraction analysis.
2004,
Pubmed
Ciesielski,
Adaptability of the Vitamin D nuclear receptor to the synthetic ligand Gemini: remodelling the LBP with one side chain rotation.
2007,
Pubmed
Collodi,
Culture of cells from zebrafish (Brachydanio rerio) embryo and adult tissues.
1992,
Pubmed
Colombo,
Differential modulation of cytochrome P-450 1A and P-glycoprotein expression by aryl hydrocarbon receptor agonists and thyroid hormone in Xenopus laevis liver and intestine.
2003,
Pubmed
,
Xenbase
Delrio,
Identification and biosynthesis of steroid hormones in the gonads of Ciona intestinalis.
1971,
Pubmed
Delsuc,
Tunicates and not cephalochordates are the closest living relatives of vertebrates.
2006,
Pubmed
Dresser,
Coordinate induction of both cytochrome P4503A and MDR1 by St John's wort in healthy subjects.
2003,
Pubmed
Dusso,
Vitamin D.
2005,
Pubmed
Farber,
Genetic analysis of digestive physiology using fluorescent phospholipid reporters.
2001,
Pubmed
Geick,
Nuclear receptor response elements mediate induction of intestinal MDR1 by rifampin.
2001,
Pubmed
Goodwin,
Regulation of cyp3a gene transcription by the pregnane x receptor.
2002,
Pubmed
Goto,
Physicochemical and physiological properties of 5alpha-cyprinol sulfate, the toxic bile salt of cyprinid fish.
2003,
Pubmed
Gronemeyer,
Principles for modulation of the nuclear receptor superfamily.
2004,
Pubmed
Grün,
Benzoate X receptors alpha and beta are pharmacologically distinct and do not function as xenobiotic receptors.
2002,
Pubmed
,
Xenbase
Hahn,
Aryl hydrocarbon receptor function in early vertebrates: inducibility of cytochrome P450 1A in agnathan and elasmobranch fish.
1998,
Pubmed
Handschin,
CXR, a chicken xenobiotic-sensing orphan nuclear receptor, is related to both mammalian pregnane X receptor (PXR) and constitutive androstane receptor (CAR).
2000,
Pubmed
Handschin,
The evolution of drug-activated nuclear receptors: one ancestral gene diverged into two xenosensor genes in mammals.
2004,
Pubmed
Haslewood,
Comparative studies of bile salts. Bile salts of the lamprey Petromyzon marinus L.
1969,
Pubmed
Heath,
Expression pattern of BXR suggests a role for benzoate ligand-mediated signalling in hatching gland function.
2000,
Pubmed
,
Xenbase
Holick,
Evolution and function of vitamin D.
2003,
Pubmed
Hutzler,
Sensitive and specific high-performance liquid chromatographic assay for 4'-hydroxyflurbiprofen and flurbiprofen in human urine and plasma.
2000,
Pubmed
Iyer,
Functional evolution of the pregnane X receptor.
2006,
Pubmed
,
Xenbase
Jones,
The pregnane X receptor: a promiscuous xenobiotic receptor that has diverged during evolution.
2000,
Pubmed
Jurutka,
Molecular and functional comparison of 1,25-dihydroxyvitamin D(3) and the novel vitamin D receptor ligand, lithocholic acid, in activating transcription of cytochrome P450 3A4.
2005,
Pubmed
Kliewer,
Regulation of xenobiotic and bile acid metabolism by the nuclear pregnane X receptor.
2002,
Pubmed
Kliewer,
An orphan nuclear receptor activated by pregnanes defines a novel steroid signaling pathway.
1998,
Pubmed
Kostrubsky,
The use of human hepatocyte cultures to study the induction of cytochrome P-450.
1999,
Pubmed
Krasowski,
Evolutionary selection across the nuclear hormone receptor superfamily with a focus on the NR1I subfamily (vitamin D, pregnane X, and constitutive androstane receptors).
2005,
Pubmed
,
Xenbase
Krasowski,
Evolution of the pregnane x receptor: adaptation to cross-species differences in biliary bile salts.
2005,
Pubmed
,
Xenbase
Lavine,
Aryl hydrocarbon receptors in the frog Xenopus laevis: two AhR1 paralogs exhibit low affinity for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).
2005,
Pubmed
,
Xenbase
Li,
Cloning and characterization of the vitamin D receptor from Xenopus laevis.
1997,
Pubmed
,
Xenbase
Lu,
Cloning and origin of the two forms of chicken vitamin D receptor.
1997,
Pubmed
Luo,
CYP3A4 induction by drugs: correlation between a pregnane X receptor reporter gene assay and CYP3A4 expression in human hepatocytes.
2002,
Pubmed
Ma,
Preparation of primary cell cultures from lamprey.
1999,
Pubmed
Maglich,
Nuclear pregnane x receptor and constitutive androstane receptor regulate overlapping but distinct sets of genes involved in xenobiotic detoxification.
2002,
Pubmed
Maglich,
The first completed genome sequence from a teleost fish (Fugu rubripes) adds significant diversity to the nuclear receptor superfamily.
2003,
Pubmed
Makishima,
Vitamin D receptor as an intestinal bile acid sensor.
2002,
Pubmed
McDonnell,
Molecular cloning of complementary DNA encoding the avian receptor for vitamin D.
1987,
Pubmed
Miller,
Comparative genomics.
2004,
Pubmed
Miranda,
Regulation of cytochrome P450 expression in a novel liver cell line from zebrafish (Brachydanio rerio).
1993,
Pubmed
Moore,
Pregnane X receptor (PXR), constitutive androstane receptor (CAR), and benzoate X receptor (BXR) define three pharmacologically distinct classes of nuclear receptors.
2002,
Pubmed
,
Xenbase
Moras,
The nuclear receptor ligand-binding domain: structure and function.
1998,
Pubmed
Nagpal,
Noncalcemic actions of vitamin D receptor ligands.
2005,
Pubmed
Nishikawa,
Molecular cloning and functional characterization of a novel nuclear receptor similar to an embryonic benzoate receptor BXR.
2000,
Pubmed
,
Xenbase
Rannug,
Certain photooxidized derivatives of tryptophan bind with very high affinity to the Ah receptor and are likely to be endogenous signal substances.
1987,
Pubmed
Reschly,
Evolution and function of the NR1I nuclear hormone receptor subfamily (VDR, PXR, and CAR) with respect to metabolism of xenobiotics and endogenous compounds.
2006,
Pubmed
Rochel,
The crystal structure of the nuclear receptor for vitamin D bound to its natural ligand.
2000,
Pubmed
Rozen,
Primer3 on the WWW for general users and for biologist programmers.
2000,
Pubmed
Schuetz,
Expression of cytochrome P450 3A in amphibian, rat, and human kidney.
1992,
Pubmed
Schuetz,
Induction of cytochromes P450.
2001,
Pubmed
Staudinger,
Coordinate regulation of xenobiotic and bile acid homeostasis by pregnane X receptor.
2001,
Pubmed
Steinmetz,
Binding of ligands and activation of transcription by nuclear receptors.
2001,
Pubmed
Suzuki,
Identification of cDNAs encoding two subtypes of vitamin D receptor in flounder, Paralichthys olivaceus.
2000,
Pubmed
,
Xenbase
Synold,
The orphan nuclear receptor SXR coordinately regulates drug metabolism and efflux.
2001,
Pubmed
Thompson,
Liganded VDR induces CYP3A4 in small intestinal and colon cancer cells via DR3 and ER6 vitamin D responsive elements.
2002,
Pubmed
Thornton,
Evolution of vertebrate steroid receptors from an ancestral estrogen receptor by ligand exploitation and serial genome expansions.
2001,
Pubmed
Thummel,
Transcriptional control of intestinal cytochrome P-4503A by 1alpha,25-dihydroxy vitamin D3.
2001,
Pubmed
Tocchini-Valentini,
Crystal structures of the vitamin D receptor complexed to superagonist 20-epi ligands.
2001,
Pubmed
Tocchini-Valentini,
Crystal structures of the vitamin D nuclear receptor liganded with the vitamin D side chain analogues calcipotriol and seocalcitol, receptor agonists of clinical importance. Insights into a structural basis for the switching of calcipotriol to a receptor antagonist by further side chain modification.
2004,
Pubmed
Tracy,
Role of cytochrome P450 2C9 and an allelic variant in the 4'-hydroxylation of (R)- and (S)-flurbiprofen.
1995,
Pubmed
Vanhooke,
Molecular structure of the rat vitamin D receptor ligand binding domain complexed with 2-carbon-substituted vitamin D3 hormone analogues and a LXXLL-containing coactivator peptide.
2004,
Pubmed
Vanhooke,
New analogs of 2-methylene-19-nor-(20S)-1,25-dihydroxyvitamin D3 with conformationally restricted side chains: evaluation of biological activity and structural determination of VDR-bound conformations.
2007,
Pubmed
Voogt,
On the sterols of some ascidians.
1975,
Pubmed
Whitfield,
Cloning of a functional vitamin D receptor from the lamprey (Petromyzon marinus), an ancient vertebrate lacking a calcified skeleton and teeth.
2003,
Pubmed
Whitlock,
Induction of cytochrome P4501A1.
1999,
Pubmed
Yagi,
A genomewide survey of developmentally relevant genes in Ciona intestinalis. III. Genes for Fox, ETS, nuclear receptors and NFkappaB.
2003,
Pubmed